Boys will be boys, eh? In the fully aged City of London, many boys refuse to grow up. On the surface, the “Ponzi Scheme” sounds like some little boy’s Lego project. Instead, this pyramid operation, which pays investors out of money from new investors rather than profit, is a game the big City Boys play. Bernie Madoff made-off with $50 billion in his game. But with these very adult sums of money, isn’t it time they grew up?

They’ve now locked him in his room as punishment. But like Dennis the Menace, Madoff has still managed to become a pest, sending Cartier watches and Tiffany’s earrings valued at more than $1 million to family and friends. This City Boy brat won’t stop his boyish games, and the spoiled shark now spoils his friends.

I’ll never forget a moment at a meeting a couple years ago when, discussing investment strategy over a conference call, we came to the subject of Bernie. When my manager asked the client, “What do you think of Madoff?” The client responded, without hesitation, “he’s a crook. I wouldn’t touch him with a ten-foot pole.” So he’s feeling pretty good about himself now.

Many others weren’t so sharp. The Madoff liquidation squad has sent over 8,000 claim forms to his victims, a list that reads like a Who’s Who of international business and high society, including Uma Thurman’s boy Arnaud Busson, Steven Spielberg, and that ultimate City Girl: hedge fund manager Nicola Horlick.

Where were his parents when he was swindling the City’s smartest? Madoff was examined at least 8 times by his supposed watchdog, the SEC. Yet in an ironic twist of fate, his boyish games were only unveiled as just that by his own two (not so little) boys.

It wasn’t just our perceptive client who picked up on Madoff’s childish games. Desks and fund managers all over the City suspected that Bernie Madoff was a fraud, but no one wanted to risk their neck by saying the emperor wasn't wearing any clothes. Savvy City fund managers kept away from him like the plague, noticed red flags and, in some cases, steered clients away from him. Merrill Lynch, Goldman Sachs, and GAM were a few of the grown-ups who saw through the Ponzi circus.

Letting boys be boys is fine when it’s just a bit of fun. But with behaviour this naughty, City Boys like Madoff need to be taught some good manners, thoughtfulness and reliability. They need to start acting like girls.